No power, popping sound from speaker.

Hey there everyone. I'm having a problem that has plagued the 3DS, the "my system if turning off and making a popping sound after 3 seconds". I have already tried reseating all of the ribbon cables and that hasn't fixed it. All of the information I can seem to find says that is the main problem. Is there any other problem that could cause these symptoms? Thanks for the help!

@Matthew McHale, It is fine if you remove the plate. It essentially works as a heat sink. The solder points around the plate fail when its dropped and when the plate is dislodge it can move around the board and make contacts with other components. This will cause the board to short out.

@castlejoshua Um can I ask something, my 2DS has this issue with the popping sound but two of the bottom screws won't come off, I'm not sure what happened but they seemed to be different screws entirely and now I can't even tell what type of screw it is now. If you could please help me

In my experience that means you probably need to install a new upper flex cable - the one with the 3D switch/speakers/sensor. Remember that cable goes in the motherboard connector gold-contact-side-up too. You might want to check inside the connector as well to make sure none of the internal pins are bent out of shape as that will cause the exact same symptoms.

Simplest thing to do is to check the back light ribbon cable. This ribbon cable is a thin ribbon cable, attached to the lcd, and connected to the bottom-right of the mother-board. If there is no sign of water damage, then re-connect the ribbon cable. If the ribbon-cable is damaged, then the back light of the lcd can be swapped out.